NHTSA documents say the affected vehicles don’t meet the side impact performance requirements for the rear seat passengers because they fail to comply with Federal Motor Vehicle Safety Standard’s “Side Impact Protection” requirement. During side-impact tests, when the rear door was hit from the side, the door panel hit the dummy in the rear seat. The force was such that it indicated a real passenger would have been hurt. The agency initially found the standard Cooper Hardtop to be compliant, however a slight variance caused the sportier S trim to fail.

The recall, issued by Mini’s parent company BMW, involves 2014-15 Cooper and Cooper S Hardtop four-door cars, along with 2015 John Cooper Works vehicles. It’s scheduled to begin in mid-September.

BMW says it’s not aware of any injuries related to the issue.

So here’s the fix. Technicians will install additional energy-absorption material between the rear interior side panels and the exterior vehicle body to help improve performance in the side-impact test and add side impact protection.

CONSEQUENCE:

If the side impact performance requirements are not met, rear seat passengers may be at a higher risk of injury during a crash.

REMEDY:

MINI will notify owners, and dealers will install additional energy absorption material between the rear interior side panels and the exterior vehicle body, free of charge. The recall is expected to begin September 12, 2015. Owners may contact MINI customer service at 1-866-825-1525. Note: this recall supersedes 14V-815.

NOTES:

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.safercar.gov.